103 lines
2.5 KiB
Go
103 lines
2.5 KiB
Go
// Copyright (C) 2015 The Syncthing Authors.
|
|
//
|
|
// This Source Code Form is subject to the terms of the Mozilla Public
|
|
// License, v. 2.0. If a copy of the MPL was not distributed with this file,
|
|
// You can obtain one at http://mozilla.org/MPL/2.0/.
|
|
|
|
package dialer
|
|
|
|
import (
|
|
"net"
|
|
"net/http"
|
|
"os"
|
|
"strings"
|
|
"time"
|
|
|
|
"golang.org/x/net/proxy"
|
|
|
|
"github.com/syncthing/syncthing/lib/logger"
|
|
"github.com/syncthing/syncthing/lib/osutil"
|
|
)
|
|
|
|
var (
|
|
l = logger.DefaultLogger.NewFacility("dialer", "Dialing connections")
|
|
dialer = proxy.FromEnvironment()
|
|
usingProxy = dialer != proxy.Direct
|
|
)
|
|
|
|
func init() {
|
|
l.SetDebug("dialer", strings.Contains(os.Getenv("STTRACE"), "dialer") || os.Getenv("STTRACE") == "all")
|
|
if usingProxy {
|
|
http.DefaultTransport = &http.Transport{
|
|
Dial: Dial,
|
|
Proxy: http.ProxyFromEnvironment,
|
|
TLSHandshakeTimeout: 10 * time.Second,
|
|
}
|
|
|
|
// Defer this, so that logging gets setup.
|
|
go func() {
|
|
time.Sleep(500 * time.Millisecond)
|
|
l.Infoln("Proxy settings detected")
|
|
}()
|
|
}
|
|
}
|
|
|
|
// Dial tries dialing via proxy if a proxy is configured, and falls back to
|
|
// a direct connection if no proxy is defined, or connecting via proxy fails.
|
|
func Dial(network, addr string) (net.Conn, error) {
|
|
if usingProxy {
|
|
conn, err := dialer.Dial(network, addr)
|
|
if err == nil {
|
|
l.Debugf("Dialing %s address %s via proxy - success, %s -> %s", network, addr, conn.LocalAddr(), conn.RemoteAddr())
|
|
if tcpconn, ok := conn.(*net.TCPConn); ok {
|
|
osutil.SetTCPOptions(tcpconn)
|
|
}
|
|
return dialerConn{
|
|
conn, newDialerAddr(network, addr),
|
|
}, nil
|
|
}
|
|
l.Debugf("Dialing %s address %s via proxy - error %s", network, addr, err)
|
|
}
|
|
|
|
conn, err := proxy.Direct.Dial(network, addr)
|
|
if err == nil {
|
|
l.Debugf("Dialing %s address %s directly - success, %s -> %s", network, addr, conn.LocalAddr(), conn.RemoteAddr())
|
|
if tcpconn, ok := conn.(*net.TCPConn); ok {
|
|
osutil.SetTCPOptions(tcpconn)
|
|
}
|
|
} else {
|
|
l.Debugf("Dialing %s address %s directly - error %s", network, addr, err)
|
|
}
|
|
return conn, err
|
|
}
|
|
|
|
type dialerConn struct {
|
|
net.Conn
|
|
addr net.Addr
|
|
}
|
|
|
|
func (c dialerConn) RemoteAddr() net.Addr {
|
|
return c.addr
|
|
}
|
|
|
|
func newDialerAddr(network, addr string) net.Addr {
|
|
netaddr, err := net.ResolveIPAddr(network, addr)
|
|
if err == nil {
|
|
return netaddr
|
|
}
|
|
return fallbackAddr{network, addr}
|
|
}
|
|
|
|
type fallbackAddr struct {
|
|
network string
|
|
addr string
|
|
}
|
|
|
|
func (a fallbackAddr) Network() string {
|
|
return a.network
|
|
}
|
|
|
|
func (a fallbackAddr) String() string {
|
|
return a.addr
|
|
}
|